Ernst served as chairman of Physical Medicine and Rehabilitation (PMR) at the University of Vienna, but left this position in 1993 to set up the department of Complementary Medicine at the University of Exeter in England. He became director of complementary medicine of the Peninsula Medical School (PMS) in 2002. Ernst was the first occupant of the Laing chair in Complementary Medicine, retiring in 2011. He was born and trained in Germany, where he began his medical career at a homeopathic hospital in Munich,[1] and since 1999 has been a British citizen.

Ernst was born in Germany in 1948. His father and grandfather were both doctors, and his mother was a laboratory assistant. Ernst originally wanted to be a musician, but his mother persuaded him that medicine might be a good "sideline" career for him to pursue.[5]

The world's first professor of complementary medicine,[4] Ernst researches complementary medicine with an emphasis on efficacy and safety. His research mainly surveys systematic reviews and meta-analyses of clinical trials; the institute has not performed a clinical trial for some time due to budget constraints.[4] He has over 700 papers published in scientific journals.[1] He has said that about five percent of alternative medicine is backed by evidence,[8] with the remainder being either insufficiently studied or backed by evidence showing lack of efficacy.

Ernst's department at Exeter defined complementary medicine as "diagnosis, treatment and/or prevention which complements mainstream medicine by contributing to a common whole, by satisfying a demand not met by orthodoxy or by diversifying the conceptual frameworks of medicine."[9]

Ernst asserts that, in Germany and Austria, complementary techniques are mostly practiced by qualified physicians, whereas in the UK they are mainly practiced by others. He also argues that the term "Complementary and Alternative Medicine" ("CAM") is an almost nonsensical umbrella term, and that distinctions between its modalities must be made.[10]

In 2005, a report by economist Christopher Smallwood, personally commissioned by Prince Charles, claimed that CAM was cost-effective and should be available in the National Health Service (NHS). Ernst was initially enlisted as a collaborator on the report, but asked for his name to be removed after a sight of the draft report convinced him that Smallwood had "written the conclusions before looking at the evidence".[11] The report did not address whether CAM treatments were actually effective and Ernst described it as "complete misleading rubbish".[11]

Ernst was, in turn, criticised by The Lancet editor Richard Horton for disclosing contents of the report while it was still in draft form. In a 29 August 2005 letter to The Times Horton wrote: "Professor Ernst seems to have broken every professional code of scientific behaviour by disclosing correspondence referring to a document that is in the process of being reviewed and revised prior to publication. This breach of confidence is to be deplored."[12]

Prince Charles' private secretary, Sir Michael Peat, also filed a complaint regarding breached confidentiality with Exeter University. Although he was "cleared of wrongdoing",[13] Ernst has said[11] that circumstances surrounding the ensuing university investigation led to his retirement.

In 2008, Ernst sent an open letter urging the Royal Pharmaceutical Society of Great Britain to crack down on high street chemists that sell homeopathic remedies without warning that the remedies lack evidence for claimed biological effects.[18] According to him, this disinformation would be a violation of their ethical code:

My plea is simply for honesty. Let people buy what they want, but tell them the truth about what they are buying. These treatments are biologically implausible and the clinical tests have shown they don't do anything at all in human beings. The argument that this information is not relevant or important for customers is quite simply ridiculous.[18]

In a 2008 interview with Media Life Magazine, when he and Simon Singh were asked this question—"What do you think the future is for alternative medicine?"—they replied:

For us, there is no such thing as alternative medicine. There is either medicine that is effective or not, medicine that is safe or not. So-called alternative therapies need to be assessed and then classified as good medicines or bogus medicines. Hopefully, in the future, the good medicines will be embraced within conventional medicine and the bogus medicines will be abandoned.[19]

In an article entitled "Should We Maintain an Open Mind about Homeopathy?"[20] published in the American Journal of Medicine, Michael Baum and Edzard Ernst—writing to other physicians—wrote some strong criticisms of homeopathy:

Homeopathy is among the worst examples of faith-based medicine... These axioms [of homeopathy] are not only out of line with scientific facts but also directly opposed to them. If homeopathy is correct, much of physics, chemistry, and pharmacology must be incorrect.... To have an open mind about homeopathy or similarly implausible forms of alternative medicine (e.g., Bach flower remedies, spiritual healing, crystal therapy) is therefore not an option. We think that a belief in homeopathy exceeds the tolerance of an open mind. We should start from the premise that homeopathy cannot work and that positive evidence reflects publication bias or design flaws until proved otherwise... We wonder whether any kind of evidence would persuade homeopathic physicians of their self-delusion and challenge them to design a methodologically sound trial, which if negative would finally persuade them to shut up shop... Homeopathy is based on an absurd concept that denies progress in physics and chemistry. Some 160 years after Homeopathy and Its Kindred Delusions, an essay by Oliver Wendell Holmes, we are still debating whether homeopathy is a placebo or not... Homeopathic principles are bold conjectures. There has been no spectacular corroboration of any of its founding principles... After more than 200 years, we are still waiting for homeopathy "heretics" to be proved right, during which time the advances in our understanding of disease, progress in therapeutics and surgery, and prolongation of the length and quality of life by so-called allopaths have been breathtaking. The true skeptic therefore takes pride in closed mindedness when presented with absurd assertions that contravene the laws of thermodynamics or deny progress in all branches of physics, chemistry, physiology, and medicine.[20]

Ernst was accused by Prince Charles' private secretary of having breached a confidentiality agreement regarding the 2005 Smallwood report. After being subjected to a "very unpleasant" investigation by the University of Exeter, in which he was "treated as guilty until proven innocent", the university accepted his innocence but continued, in his view, to treat him as "persona non grata". All fundraising for his unit ceased, forcing him to use up its core funding and allow its 15 staff to drift away.[11] He retired in 2011, two years ahead of his official retirement.[7][21] In July 2011, a Reuters article described his "long-running dispute with the Prince about the merits of alternative therapies" and stated that he "accused Britain's heir-to-the-throne Prince Charles and other backers of alternative therapies on Monday of being 'snake-oil salesmen' who promote products with no scientific basis", and that the dispute "had cost him his job - a claim Prince Charles's office denied".[22]

In 2001, Ernst sat on the Scientific Committee on Herbal Medicinal Products of the Irish Medicines Board.[24] In 2005, he was a member of the Medicines Commission of the British Medicines Control Agency (now part of the MHRA) which determines which substances may be introduced and promoted as medicine.[25] In 2008, he was an external examiner for several university medical schools in several countries.[26] He is a Founding Member and on the Board of the Institute for Science in Medicine, formed in 2009.[2]